CN102332261B - Audio end-to-end delay measuring method and device based on nonintrusive double-end collection - Google Patents
Audio end-to-end delay measuring method and device based on nonintrusive double-end collection Download PDFInfo
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- CN102332261B CN102332261B CN2011102674363A CN201110267436A CN102332261B CN 102332261 B CN102332261 B CN 102332261B CN 2011102674363 A CN2011102674363 A CN 2011102674363A CN 201110267436 A CN201110267436 A CN 201110267436A CN 102332261 B CN102332261 B CN 102332261B
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Abstract
The invention provides an audio end-to-end time delay measuring method and device based on nonintrusive double-end collection, wherein the audio end-to-end time delay measuring method comprises the following steps of: placing a primary measuring device locally, placing an auxiliary measuring device at a far end, and connecting the two devices by virtue of a network or a special line; enabling the microphone of the auxiliary measuring device to approach the far-end loudspeaker of a system to be measured at the far end; measuring a time difference according to an audio measuring signal sent out by a local signal generator, and measuring the time difference according to an audio measuring signal sent out by a far-end signal generator; and calculating an audio end-to-end time delay by virtue of the primary measuring device. The primary measuring device provided by the invention comprises an audio test signal generator, an audio multichannel collecting module, a network receiving module, an audio time delay measuring unit and a data storing and displaying unit. The auxiliary measuring device provided by the invention comprises an audio test signal generator, an audio multichannel collecting module and a network sending module.
Description
Technical field
The present invention relates to computer media Information Communication, QoS qos measurement, particularly relate to audio frequency end-to-end delay measuring method and device that a kind of non-intervention type both-end gathers.
Background technology
Along with based on network multimedia service is used fast-developing and popularizes, the systems such as network audio-video program request, network audio-video meeting are popular rapidly.The user has proposed more and more higher requirement to the QoS service quality of network multimedia business.How can be fast, convenient, accurately the key qos parameter of candidate products is made assessment, be the key of successfully selecting best product.
Simultaneously, research and development and produce the network multimedia business and the manufacturer of system also need a kind of device to measure the key parameter of the own network multimedia product of producing quickly and easily, in order to measure key parameter in product development process, and improvement at any time.
End-to-end time delay is one of critical performance parameters of multimedia service, and it directly affects the assessment of QoS and user's experience.End-to-end time delay generally includes and gathers time delay, coding time delay, network transfer delay, decoding time delay, Playout delay etc.
The method of existing detection end-to-end time delay roughly can be divided into two large classes: a class belongs to insertion type, namely by inject the measuring-signal of feature at an end of the signal transmission path of system under test (SUT), perhaps additional measurement data on the original signal data of system under test (SUT), then extract measurement data and record the time that receives at the other end, relatively the difference of two times is obtained the time delay size.
The principal feature of this class insertion type method is need to get involved in the signal transmission path of system under test (SUT), adds wherein data or therefrom extracts measurement data, has being connected of physical circuit between measurement mechanism and equipment under test.
The Major Difficulties of this class invasive measurement method is:
At first, the Frame or the packet that usually depend on system under test (SUT) due to measurement data are transmitted, and middle inevitable through links such as compression coding, encapsulation, decapsulation, decodings, measurement data may lose or damage in compression coding and decompression procedure;
Secondly, because data layout, encapsulation format, compression coding and the decoding algorithm of system under test (SUT) may not disclose, the tester will design the metering system and the measuring-signal that match can be more difficult.
The 3rd, the invasive measurement method usually requires serial connection tap or tandem head on the signal data path of system under test (SUT), and is for the system under test (SUT) that has installed, usually cumbersome or be not allowed to.
In addition, the tool software that some invasive measurement methods need to operating measurement be used on the terminal of system under test (SUT) carries out timing by tool software.This mode may affect the normal operation of system under test (SUT) terminal itself, can only use in exploitation and debug phase at most, and be difficult to be used in the system of commercialization.
Another kind of method of testing is non-intervention type, does not have physical contact between system under test (SUT) and measurement mechanism, and system under test (SUT) is considered as black box, and test signal is mainly to enter system under test (SUT) by the sound and optic signal mode, and exports with sound, light mode.Measurement mechanism by contrast and analysis input, output signal obtains the time delay size.The advantage of these class methods is the actual motions that stay out of system under test (SUT), and is irrelevant with the system under test (SUT) specific implementation, so have applicability the most widely.Such as subjective sensation and the sense of hearing by human eye, people's ear, assessing end-to-end time delay is exactly these class methods.
Although utilize human eye, people's ear to come subjective evaluation and test very directly perceived, exists in the relatively more approaching situation of the end-to-end time delay parameter of very large error, especially two kinds of systems under test (SUT), be difficult to make science and judge accurately, cause measurement result to lack persuasion.
Summary of the invention
The object of the invention is to overcome the shortcoming and defect of above-mentioned prior art, audio frequency end-to-end time delay measuring method and the device of non-intervention type double-end signal is provided.
The present invention adopts non-intervention strategy, and system under test (SUT) is used as black box, for system under test (SUT) end to end the audio frequency time delay designed the measuring technology scheme.
The technical scheme that audio frequency end-to-end time delay of the present invention is measured comprises the steps:
(1) proving installation is made of jointly the main measurement mechanism of this locality and the aided measurement device of far-end, and main measurement mechanism gathers the local test signal, and aided measurement device gathers the test signal of far-end and is returned to main measurement mechanism by network or special line.
(2) local measuring signal generator sends the audio-frequency test signal, and this signal is gathered by the audio collecting device (as: microphone) of the local terminal of the audio collecting device of main measurement mechanism (as: microphone) and system under test (SUT) simultaneously.
(3) the audio-frequency test signal that enters system under test (SUT) local terminal microphone arrives the loudspeaker of distance terminal through processing and Internet Transmission.The signal that enters main testing apparatus audio collecting device direct measured device reads, the time that main measurement mechanism record reads
(4) microphone of far-end aided measurement device near far-end loudspeaker, receives the testing audio of far-end loudspeaker, after coding, passes local main measurement mechanism back by network.
(5) local main measurement mechanism receives the test audio signal that aided measurement device is passed back, the time that this signal received in record
, submit to signal processing unit to carry out analytical calculation after decoding.
(6) local main measurement mechanism is identified the audio-frequency test signal of successively receiving, calculates time difference between the two, is designated as
(7) measuring signal generator of far-end sends the audio-frequency test signal, and this signal is inputted the microphone of the distance terminal of the microphone of far-end aided measurement device and system under test (SUT) simultaneously.
(8) the signal process that enters the microphone of system under test (SUT) distance terminal is processed and Internet Transmission, arrive the loudspeaker of local terminal, after main measurement mechanism collection by this locality, the entering signal processing unit carries out analysis and calculation, the time that this audio frequency measuring-signal received in main measurement mechanism record
(9) the audio-frequency test signal that enters far-end aided measurement device microphone is returned to main measurement mechanism by network or special line, then is submitted to signal processing unit and carries out analytical calculation, the time that this audio frequency measuring-signal received in main measurement mechanism record
(10) signal processing unit of local main measurement mechanism according to the time of step (8) and step (9) record, calculates time difference between the two
.
(11) signal processing unit of main measurement mechanism is according to two time differences of step (6) and the acquisition of (10) priority
With
, the audio frequency end-to-end time delay of calculating system under test (SUT)
Measurement mechanism of the present invention comprises main measurement mechanism and aided measurement device, realizes communication by network or special line between the two.
Aided measurement device of the present invention comprises following assembly:
(1) audio signal generator 101, and periodicity or disposable generation preset the audio-frequency test signal of frequency and pattern, and are responsible for this test signal is played back.
(2) sound signal multi pass acquisition module 102 utilizes microphone to gather the audio-frequency test signal of local audio-frequency test signal and process system under test (SUT).
(3) the network sending module 103, send by network the data test signal that collects to main measurement mechanism.
Main measurement mechanism of the present invention comprises following assembly:
(1) audio signal generator 201, and periodicity or disposable generation preset the sound signal of frequency and pattern, and are responsible for this sound signal is played back.
(2) sound signal multi pass acquisition module 202 utilizes microphone to gather the audio-frequency test signal of local audio-frequency test signal and process system under test (SUT).
(3) the network receiver module 203, receive from network the data test signal that aided measurement device sends.
(4) the audio frequency time-delay measuring unit 204,, and signal time delay added up and calculated by voice-frequency-multichannel acquisition module, network receiver module input audio signal from respectively.
(5) data storage and display unit 205, the audio reception delay data outputs results on the memory device and display device of appointment.
Audio frequency end-to-end time delay measuring method and the measurement mechanism of non-intervention type double-end signal of the present invention collection have the following advantages:
(1) the inventive method is non-intervention type, and system under test (SUT) is considered as black box, and method of testing is not subjected to the impact of the factors such as the inner structure, data type, network type, code decode algorithm, function implementation of system under test (SUT).
(2) the audio frequency end-to-end time delay measured of the inventive method has comprised from audio collection until audio frequency is play the time delay summation in interior all links, and the time delay of assessing when doing subjective sensation and evaluation and test with the user is in full accord aspect content and type.
(3) measurement mechanism of the inventive method forms with the aided measurement device that is positioned at far-end by being positioned at local main measurement mechanism.Be connected by network between utility appliance and main equipment, form an audio-frequency test signal propagation path.Together with the audio data transmission path of this path and system under test (SUT), consist of the propagation circuit of test signal, can solve the occasion of being inconvenient to provide the test signal propagation circuit of system under test (SUT) own, such as:
(3a) terminal of system under test (SUT) far-end, loudspeaker and microphone are all in position, be difficult to mutually near or mutually over against forming the measuring-signal loop;
(3b) terminal of system under test (SUT) far-end or microphone have been opened echo elimination/inhibit feature, can't utilize self loudspeaker formation audio-frequency test signal propagation circuit.
(4) utilize method of the present invention, the measuring signal generator of local side measuring signal generator and far-end produces respectively test signal separately, and each test signal divides two-way to enter main measurement mechanism, obtains a time difference, is respectively
With
, final measurement result handle
With
Divided by 2, just the propagation delay between main measurement mechanism and aided measurement device is cancelled out each other after addition.And the result of both additions both comprised the travel path from this locality to the far-end, also comprised the travel path from the far-end to this locality.Even there is the whereabouts path in transmission network and returns asymmetric to the performance in path, after also can postponing by counter circuit, obtain a comprehensive mean value divided by 2, eliminate the impact of this asymmetry, the result after average can reflect the actual performance of end-to-end time delay more accurately.
(5) the inventive method can make measuring signal generator continue to produce characteristic signal within a period of time, utilize measurement mechanism to carry out continuance test, obtain a series of delay data, therefrom analyze the statistical natures such as maximum delay, minimal time delay and average delay, can more fully reflect the performance change under the heterogeneous networks load condition of end-to-end time delay.
Description of drawings
When Fig. 1 is the application local audio measuring signal generator of the present invention's one example, audio frequency end-to-end time delay test philosophy schematic diagram;
When Fig. 2 is the application far-end audio measuring signal generator of the present invention's one example, audio frequency end-to-end time delay test philosophy schematic diagram;
Fig. 3 is the aided measurement device inner structure schematic diagram of the present invention's one example;
Fig. 4 is the main measurement mechanism inner structure schematic diagram of the present invention's one example.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, but embodiments of the present invention are not limited to this.
Embodiment 1, and Fig. 1, Fig. 2 have provided the principle schematic of the audio frequency end-to-end time delay test of non-intervention type double-end signal collection.
As Fig. 1, audio frequency end-to-end time delay measuring method of the present invention comprises:
Step 1 is placed a main measurement mechanism in this locality, place an aided measurement device at far-end, realizes communication by network or special line between two equipment; Main measurement mechanism gathers local signal, and aided measurement device gathers remote signaling and is returned to local main measurement mechanism.
(1) microphone of the main measurement mechanism in this step 1 near the loudspeaker of local terminal, guarantees accurately to gather the audio-frequency test signal that the local terminal loudspeaker sends.
(2) microphone of the aided measurement device in this step 1 near the loudspeaker of distance terminal, guarantees accurately to gather the audio-frequency test signal that the distance terminal loudspeaker sends.
Step 2, local audio-frequency test signal generator sends test audio signal, and this signal is inputted the microphone (as shown in the position A in Fig. 1) of the local terminal of system under test (SUT) and the microphone (as shown in the position B in Fig. 1) of measurement mechanism simultaneously.
(1) signal that also enters simultaneously the local audio collecting device of the audio-frequency test signal in this step 2 is directly read (as shown in the position B in Fig. 1) by main measurement mechanism.
(2) the audio-frequency test signal in this step 2 enters the local terminal microphone, through processing and Internet Transmission, arrives the loudspeaker (as shown in the position C in Fig. 1) of distance terminal through signal.
Step 3, the audio-frequency test signal that far-end loudspeaker is play, the microphone through the far-end aided measurement device enters far-end aided measurement device (as shown in the position D in Fig. 1).
Enter the audio-frequency test signal of far-end aided measurement device in this step 3, through after compression coding, pass this landlord measurement mechanism back by Internet Transmission, successively the position E in approach Fig. 1 and position F.
Step 4, local main measurement mechanism receives the testing audio that the far-end aided measurement device is passed back, submits to signal processing unit to carry out analytical calculation after decoding.
Step 5, local main measurement mechanism is identified the test audio signal of successively receiving for twice, calculates time difference between the two, is designated as
The time difference that calculates in this step 5
Be mainly two parts time delay and, i.e. the One Way Delay of A → C
And the One Way Delay of D → E → F
, namely have
Step 6, far-end audio measuring signal generator in Fig. 2 sends the audio-frequency test signal, and this signal is inputted the microphone (as shown in the position C of Fig. 2) of the distance terminal of system under test (SUT) and the microphone (as shown in the position D of Fig. 2) of far-end aided measurement device simultaneously.
Step 7, the signal process that enters the microphone of system under test (SUT) distance terminal is processed and Internet Transmission, arrive the loudspeaker (as shown in the position A of Fig. 2) of local terminal, after the main measurement mechanism of this locality gathers (as shown in the position B of Fig. 2), the entering signal processing unit carries out analysis and calculation.
Step 8, the audio-frequency test signal that enters far-end aided measurement device microphone arrives this landlord measurement mechanism by Internet Transmission, and successively the position E in approach Fig. 2 and position F, then be submitted to signal processing unit and carry out analytical calculation.
Step 9, the signal processing unit of local main measurement mechanism is identified the test audio signal from the remote signaling generator of successively receiving, calculates time difference between the two, is designated as
The time difference that calculates in this step 9
Mainly the poor of two parts time delay, i.e. the one-way latency of C → A
Poor with D → E → F one-way latency
, namely have
.
Step 10, the signal processing unit of main measurement mechanism is according to two time differences of step (5) and the acquisition of (9) priority
With
, the audio frequency end-to-end time delay of calculating system under test (SUT)
.
In this step 10
,
, both add up to:
The result that obtains is the mean value of A à C time delay and C à A time delay.
Embodiment 2, and Fig. 3 has provided the organigram of aided measurement device
As Fig. 3, the aided measurement device of audio frequency end-to-end time delay of the present invention comprises:
(1) assembly 1, and the audio-frequency test signal generator is responsible for producing the audio-frequency test signal.This signal can be analyzed and be identified by measurement mechanism.
(2) assembly 2, and the voice-frequency-multichannel acquisition module is responsible for the multichannel voice frequency test signal that input separates or mixes.
(3) assembly 3, and the network sending module is responsible for the measuring-signal data that collect are sent to main measurement mechanism by network.
Embodiment 3, and Fig. 4 has provided the organigram of the main measurement mechanism of audio frequency end-to-end time delay
As Fig. 4, the main measurement mechanism of audio frequency end-to-end time delay of the present invention comprises:
(1) assembly 1, and the audio-frequency test signal generator is responsible for producing the audio-frequency test signal.This signal can be analyzed and be identified by measurement mechanism.
(2) assembly 2, and the voice-frequency-multichannel acquisition module is responsible for the multichannel voice frequency test signal that input separates or mixes, and with the sound signal input audio frequency time-delay measuring unit that collects.
(3) assembly 3, and the network receiver module is responsible for receiving the measuring-signal that the far-end aided measurement device sends.
(4) assembly 4, and the audio frequency time-delay measuring unit is responsible for the sound signal of input is analyzed, identifies, compared and measures, and concrete steps comprise:
Step 1, mixed multiplex audio-frequency test signal to the input of voice-frequency-multichannel acquisition module is analyzed,, need to identify exactly the audio-frequency test signal from the signal of receiving, and record its time unavoidably with noise due to the audio-frequency test signal after postponing.
Step 2, poor computing time for the measuring-signal that local signal generator sends, be designated as
, wherein
,
Be the One Way Delay of A à C,
One Way Delay for D à E à F.
Step 3, poor computing time for the measuring-signal that the remote signaling generator sends, be designated as
, wherein
,
Be the one-way latency of C à A,
Be D à E à F one-way latency.
Step 4, the end-to-end time delay of calculating system under test (SUT)
, be submitted to data storage and display unit.
Above-described embodiment is the better embodiment of the present invention; but embodiments of the present invention are not restricted to the described embodiments; other any do not deviate from change, the modification done under Spirit Essence of the present invention and principle, substitutes, combination, simplify; all should be the substitute mode of equivalence, within being included in protection scope of the present invention.
Claims (1)
1. the audio frequency end-to-end time delay measuring method of non-intervention type both-end collection, is characterized in that comprising the steps:
(1) the local audio test signal is gathered by main proving installation and system under test (SUT) local side audio collecting device simultaneously; System under test (SUT) is delivered to far-end with the audio-frequency test signal; Main proving installation record collects the time of this audio-frequency test signal;
(2) auxiliary test unit receives the audio-frequency test signal that arrives the loudspeaker of far-end through system under test (SUT), then is returned to main proving installation, and records by main proving installation the time that this audio-frequency test signal is passed back;
(3) determine mistiming Δ T according to two times of step (1), step (2) record
AL
(4) the far-end audio test signal is gathered by auxiliary test unit and system under test (SUT) far-end audio collecting device respectively simultaneously, and passes respectively main testing apparatus and system under test (SUT) local side back;
(5) main proving installation gathers the audio-frequency test signal of system under test (SUT) local side by audio collecting device, and record collects the time of this audio-frequency test signal;
(6) main proving installation receives the audio-frequency test signal of auxiliary test unit, the time that this audio-frequency test signal received in record;
(7) determine mistiming Δ T according to two times of step (5), step (6) record
AR
(8) main proving installation is according to step (3), two definite time Δ T of step (7)
AL, Δ T
ARDetermine the audio frequency end-to-end time delay.
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| CN103391343B (en) * | 2013-07-20 | 2015-06-03 | 青岛歌尔声学科技有限公司 | Bluetooth phone function test system and method of Bluetooth multimedia |
| CN105450882B (en) * | 2015-11-13 | 2018-07-20 | 公安部第三研究所 | A kind of audio conversion characteristic test method |
| CN105472190A (en) * | 2015-11-13 | 2016-04-06 | 公安部第三研究所 | Audio signal time delay testing method |
| CN109728864B (en) * | 2018-12-26 | 2022-08-30 | 刘科宏 | System loss testing method based on antenna measuring system |
| CN110365555B (en) * | 2019-08-08 | 2021-12-10 | 广州虎牙科技有限公司 | Audio delay testing method and device, electronic equipment and readable storage medium |
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